Distribution and use of electricity throughout the home. Electrical standards vary greatly worldwide, so providing your location in your question or your profile helps ensure you get answers that are relevant to you.

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6
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4answers
2k views

How Do I Plan for an Intrusion Detection System?

I would like to plan for an intrusion detection system in a home that is currently under construction. The home has a walkout basement that is sloping, shown in the rear elevation picture shown ...
4
votes
1answer
677 views

Replacing Halogen with LED bulbs

I've just purchased some 12V LED MR-16 bulbs, intending to use them to replace the existing 12V Halogen MR-16 bulbs in my bathroom. I have found, much to my chagrin, that the LED bulbs seem to have ...
3
votes
3answers
690 views

What are some computer interfacing electric energy meters on the market?

Does computer interfacing electric energy meters exist? With possibilities to get/log current power usage and monthly used kilowatt hours. With ethernet/rs232 etc interface. I am looking for this for ...
17
votes
8answers
12k views

Why are “Wire Nuts” not used in the UK?

I have never seen a wire nut used in the UK, but they seem to be very common in the USA, why?
13
votes
3answers
4k views

Is there a device that will allow a bathroom fan to run for 5 minutes after it is switched off?

There is one switch that controls the lights and fan in the bathroom. Users turn the light/fan on when they enter, and off when they leave. I'd like for the bathroom fan to run for a time after they ...
12
votes
4answers
37k views

How do I properly wire GFCI outlets in parallel?

I have two countertop outlets in my kitchen that I am in the process of replacing with new, GFCI-protected outlets. These two outlets are on a circuit together, and they are the only loads on that ...
10
votes
1answer
2k views

How to replace a standard 2-gang light switch with an electric dimmer switch

I'm looking for a some assistance in fitting a new electric dimmer light switch. I'm in the UK if that makes a difference. I am trying to replace my existing two-gang light switch with a LightWaveRF ...
7
votes
2answers
2k views

How can I determine if my outlets can easily be grounded?

I'm not sure what to do here. I just moved into a building and my outlets are all 2 prong outlets. Here is what I know of for sure: All the outlets are 2 prong outlets The bathroom outlet has the ...
7
votes
4answers
4k views

Can I replace an outlet that uses knob and tube wiring with a grounded outlet?

Can I replace an outlet that uses knob and tube wiring with a grounded outlet? Obviously the best choice would be to replace the old wiring. Is there a standard way to ground these outlets? Do I need ...
4
votes
1answer
442 views

What should I do about old cables that have been damaged?

I was replacing some drywall and noticed the wiring underneath has a couple of surface tears. House is from the sixties, but has been rewired with new Romex, except this circuit. Wire seems to be old ...
4
votes
1answer
2k views

How do I install electrical through stucco

Is there such a thing as an "old work" stucco junction box? Rather than cutting and flashing a 4" hole for a new junction box, can I cut a 1/2 hole for the non-metallic cable, and attach some sort of ...
13
votes
3answers
1k views

Is there ever a reason for reversing hot and neutral on a receptacle?

I moved into a new home and several receptacles have the hot and neutral reversed. I confirmed this with a basic receptacle tester. I opened one up and found the white wire on the brass terminal, ...
13
votes
3answers
1k views

Can I safely use a switch rated for “1A at 125V” with 240V, assuming I stay below 125W?

I recently purchased a foot switch for a standing lamp. The switch is rated for 1A at 125V. I would like to use this switch with a low energy lamp (typically 10W or below) but with a 240V supply. Is ...
12
votes
3answers
10k views

Are both legs of a home's power supply equally used?

This is basically just to satisfy my curiosity. Please correct me if I'm wrong about any of this: I believe power supply to a home's main panel usually consists of: A neutral wire A hot wire 120 ...
12
votes
3answers
628 views

What is “knob and tube wiring”?

I assume this is some USA wiring system, am I right?
11
votes
3answers
1k views

What size extension cord should I use for multiple computers?

We're hosting a LAN party (several computers, 50+) and I had some questions about power draw; I hope this is the right place to ask. Currently, we're assuming each PC will draw an average of 3.5 ...
11
votes
7answers
904 views

What's the least intrusive way to find out what's in a wall?

I'm getting ready to mount a flatscreen TV on our living room wall and would like to route various cables through it (e.g. surround sound speakers, HDMI, etc). I appreciate the AWESOME tips here, but ...
10
votes
1answer
622 views

Humming Ceiling Fans

I have two Harbor Breeze 52in. Builders Series Ceiling Fans. Under normal operation these fans are smooth and quiet. However, during power outages like we've had recently, I use a Devilbiss 6000 ...
10
votes
4answers
685 views

How do I use three-prong appliances when my outlets are mostly two-prong?

I am living in a house where most electrical outlets are two prong. There are a smattering of three prong, in particular where an addition was put on. Am I hosed when it comes to where I can plug in ...
9
votes
2answers
5k views

How can I add a circuit breaker when there are no openings available in the neutral bus bar?

I'm trying to add a 20 amp circuit breaker into my existing main panel. The main panel has one vacant slot to put the breaker, but the neutral and ground bars have no more vacant slots. My question is ...
9
votes
5answers
49k views

How do I add more circuit breakers once the breaker box is full?

My house was completely rewired by the previous owner. They tore out all the old knob-and-tube and replaced it with modern wiring. I definitely appreciate this, but unfortunately they left ...
8
votes
1answer
35k views

Why is my air conditioner tripping the circuit breaker?

Our air conditioner recently stopped blowing out cold air. When I went to check on it, I noticed that the outside unit wasn't coming on. We had had problems with ants in the contacter in the past, ...
8
votes
3answers
4k views

Can I use two wire nuts instead of one to connect 6 wires inside a 3-gang box?

Is it considered acceptable practice to use two wirenuts in a situation where it is possible to use only one but may be easier to use two? I have a three-gang box with six cables coming into it. The ...
8
votes
1answer
2k views

How can I trace cable through floors and walls?

How can I work out where an electrical cable runs through walls/floors? I am building a circuit map of a 1941 house with unfinished basement. I shut off all circuits at the main service panel, switch ...
8
votes
2answers
3k views

How can I stop bulbs from buzzing when dimmed?

I've got some hanging lights with "Fat Albert" bulbs that are plugged into a dimmer switch. When they're dimmed to certain levels, the bulbs make a soft buzzing sound. The buzz is amplified and ...
7
votes
5answers
3k views

Why do electricians prefer not to use the push-in connections on receptacles?

Why do electricians prefer not to use the back-stab or quick connect holes on switches and receptacles? If these were unreliable do you think they would be allowed by the NFPA and NEC?
7
votes
2answers
509 views

Why were only some of my tools damaged when connected to a 240V receptacle?

I live in the US and recently bought a home. There are several electrical outlets in my garage. I have recently had two tools that have burned up and gone to an early grave. It turns out that the ...
7
votes
1answer
1k views

Any reason not to ground the sheathing of MX wire?

Having recently bought an older house (c1943) I am doing a little work on the place. While rewiring a light switch I noted that there is newer Romex wiring from the distribution panel to the switch, ...
7
votes
1answer
21k views

Light switch setup using only hot wire. Is it normal?

I was changing the light switches around the house when I came upon this setup. The two switches to the right are all wired using the hot wire (black) from the two electrical wire on the back panel. ...
7
votes
3answers
4k views

How can I improve the wiring under the sink for a garbage disposal?

My vegetable sprayer line broke yesterday, which led me underneath my sink. It wasn't until I was kneeling in a large puddle of water with the line draining on me and the floor that I realized how bad ...
7
votes
3answers
3k views

What to do with an apartment with only 2-pronged outlets

I just rented an apartment (Colorado, for what it's worth RE code) that has 2-pronged outlets throughout the place except for two GFCI's, one in the bathroom and one in the kitchen. I bought the ...
7
votes
2answers
1k views

Are there any “easy” ways to trace a home electrical system?

We bought a home a few months ago, and the electrical panel (and subpanel) are completely unlabelled. We have no way, short of flipping breakers, to know what breaker powers which fixtures. Is there a ...
6
votes
3answers
2k views

Are extension cords safe for permanent use?

I recently learned (via a rant from an electrician's son and some internet research) that the standard buy-anywhere cheapo extension cords are a big cause of electrical fires and are not recommended ...
6
votes
2answers
547 views

Does lamp maximum wattage matter for CF bulbs? [duplicate]

Say I have a table lamp that states (via a slightly scary sticker) that it takes a 60W max bulb. Of course, that was based around incandescent wattages. Is there any risk with putting in a CF bulb ...
6
votes
2answers
7k views

Why does my fluorescent light fixture take minutes to turn on in high heat and humidity?

Our kitchen fixture won't come on for 3 to 5 minutes when the temperature goes over 90°F (32.2°C) and 90% humidity. It flickers and only reaches 80% brightness after that. It will occasionally ...
6
votes
5answers
13k views

Is there an NEC-compliant method of repairing minor damage to electrical wire insulation without a junction box?

While trying to pry loose a stubborn cable staple that fastens a 14-gauge electrical cable to a stud, I accidentally tore a very small hole through both the outer jacket and the insulation around the ...
5
votes
3answers
10k views

How can I rewire my bathroom fan, light, and receptacle?

My bathroom has one switch that powers the fan and light. In that electrical box, there is also a hard wired electrical outlet that sits in the bathroom. Since I don't have room for a 2 gang box in ...
5
votes
2answers
5k views

How to determine the correct capacity for a sub-panel for a shop?

I plan to install a sub-panel for my woodworking shop, and would like to determine the total capacity that should supply that sub-panel. These are the main items that will likely be running in the ...
5
votes
1answer
2k views

Can I replace an old exhaust fan and connect it to an existing light switch?

I just purchased a new home and in one of the bathrooms there is an old exhaust fan and two light switches. There is a recessed light located in the ceiling above the shower and another light above ...
5
votes
2answers
4k views

What about a light switch in the closet?

Okay you guys I have next question. And like all good questions this one begins with a story. I was reading the post about a nick in a wire and read a couple of you mention that light switch in a ...
5
votes
1answer
816 views

How to deal with abandoned wire?

There is a 240V/30A circuit in a room of my house that used to be a patio. I think it was used for a baseboard/electric heater system. It had a surface mounted outlet that I have removed, but now I ...
5
votes
3answers
840 views

What's the best way to label a double gang box with two circuits

I'm installing some lights in my basement, and will be replacing the single gang box in the hall (currently only for hall light) with a double gang box. The idea is to accommodate the hall light ...
5
votes
7answers
4k views

How can I create circuit diagrams and what program should I use?

Circuit diagrams are very handy. On this site, they can really help illustrate the problem or solution (see here). They can help you visualize what needs to be changed when doing work on your house, ...
4
votes
1answer
104 views

How can I repair a ceiling fan that hums, but doesn't turn?

The ceiling fan/light has power. The lights work, but the fan doesn't turn even though it hums. Why is this, and how can I fix it?
4
votes
1answer
146 views

What's the recommended procedure for converting a single circuit light switch into two switches for controlling a bathroom fan?

I think my question might be similar to Controlling two fixtures on same circuit independently but I don't need anything as fancy. Summary: I'm remodeling a bathroom. Presently it has one switch ...
4
votes
2answers
1k views

What type of wire should I use to feed a 70 ampere subpanel?

Finishing a basement and I need to add a subpanel. Main panel is outside. Subpanel will be in the basement. 70 Amp breaker in the main to feed the subpanel. I was thinking THHN but would this mean ...
4
votes
4answers
1k views

If neutral carries current back to the breaker panel, why doesn't it need to be connected to a switch?

I've got some limited field experience as an electrical helper, but no real classroom experience yet. (saving up for school) I am of the understanding that the neutral wire carries electricity back ...
4
votes
5answers
26k views

How much energy will continuously running a furnace fan use?

We have a bi-level (tri-level? There's a small entry way and utility room, then an upstairs living area and master bedroom and a downstairs living area with bedrooms) in mid-Michigan. The downstairs ...
4
votes
2answers
1k views

Can my apartment's electricity harm my computer? Is there an easy way to test the electricity?

I live in a (rented, 1980 built) row townhouse in the USA with slightly suspect electricity: A few of the outlets and light switches in the house (in various rooms) don't work at all. (Even ...
3
votes
2answers
4k views

Can I install a Subpanel (in a seperate building) using a 3 wire connection (2 hots and 1 grounded neutral)?

Can I use a 3 wire connection (2 hots and 1 grounded neutral) to install a subpanel in a seperate structure if I install a seperate ground rod to the grounding bus in subpanel? I have 8/3 w/o ground ...